This chapter describes a modification to the laser flash method that allows determining temperature diffusivity and nondestructive testing of materials and constructions without cutting samples of predefined geometry. Stepwise local heating of the studied object surface at a small spot around 0.1 mm radius with simultaneous high temporary-spatial resolution infrared (IR) filming of the transient temperature distribution evolution with a thermal camera provides a wide range of possibilities for material characterization and sample testing. In case of isotropic and macroscopic homogeneous materials, the resulting transient temperature distribution is radially symmetric that renders possible to improve temperature measurement accuracy by averaging many pixels of the IR images located at the same distance from the heating spot center. The temperature diffusivity measurement can be conducted either on thin plates or on massive samples. The developed emissivity independent in plain IR thermographic method and mathematical algorithms enable thermal diffusivity measurement for both cases with accuracy around a few per cent for a wide range of materials starting from refractory ceramics to well-conducting metals. To detect defects, the differential algorithm was used. Subtracting averaged radial symmetric temperature distribution from the original one for each frame makes local inhomogeneities in the sample under study clearly discernible. When applied to crack detection in plates, the technique demonstrates good sensitivity to part-through cracks located both at the visible and invisible sides of the studied object.

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A functional diagram of a robotic complex mock-up for rejecting ball-shaped objects transported on a roller conveyor is presented. The software of the complex is designed to detect an object on the conveyor and determine its coordinates. To detect objects of control, their images obtained in the visible range of the optical spectrum and Viola–Jones object detection algorithms are employed. The developed software is based on a trained cascade classifier, the optimal settings of which are determined. To detect surface defects of objects, their spectrograms obtained in the range of 400… 1000 nm are used. The presented results can be applied to the process automation of sorting fruits and vegetables and other ball-shaped objects.

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This paper describes the new method and the device for measuring the effective thermophysical characteristics of the investigated fluid under shear flow conditions at a fixed shear rate in the gap between coaxial cylinders. The shear flow is provided by the rotation of the outer cylinder while the inner cylinder remains stationary. The measuring unit can measure the complex rheological and thermophysical characteristics of liquids in less than 30 minutes. This article describes a two-step measurement method. The first step involves the measurement of the excess temperature established because of the heat source action due to the viscous friction in shear flow of the test liquid in a layer between the cylinders; the function of the dissipative heat source in the fluid at this stage is based on the power-law. The second step includes the thermal effect on the liquid layer from the heat source (electric heater) in the inner cylinder and the registration of the temperature response in the inner cylinder layer near the heater. The experimental determination results of polyoxyethylene solution thermophysical characteristics with the addition of nanocarbon material “Taunit” are presented here.